1. Field of the Invention
The invention relates in general to housing and a light emitting device having the same, and more particularly to a housing with good heat dissipation efficacy and a light emitting device having the same.
2. Description of the Related Art
Currently, light emitting diode (LED) lamp has replaced the traditional fluorescent bulb lamp for some advantages such as higher lifespan, lower power consumption and smaller size. A LED lamp requires a light housing for fixing and protecting the LEDs. The heat dissipating efficacy of the light housing is important since the LEDs can be damaged by the thermal generating from the LEDs. Typically, a heat spreader is disposed on the heat dissipating side of the light housing for promoting the heat dissipating efficacy of the light housing.
In one type of the conventional LED lamp on street, heat spreader is exposed to the outside. This exposed heat spreader increases the surface area of the heat dissipating surface on the housing of the LED lamp, and remains the light emitting surface of the LED lamp at relatively low temperature when the high power LEDs on the light emitting surface of the LED lamp are working. However, the dust and sand are easily deposited on the gap of the exposed heat spreader.
FIG. 1A˜1B show a diagram illustrating another conventional housing of a LED lamp. Another type of the conventional LED lamp 2 utilizes an existing shell 20 of light lamp for covering and encircling the heat spreader 22 to protect the heat spreader 22 from sand and dust. This type of LED lamp put the heat spreader 22 instead of the traditional light bulb (not shown) inside the existing shell 20 of light lamp. However, heat dissipating efficacy of the LED lamp 2 is unsatisfactory for the market requirements, since a large amount of the heat air surrounding the heat spreader 22 are also encircled in the existing shell 20 of light lamp, and the large amount of heat air in this existing shell 20 of light lamp is against the object of heat dissipating.